This invention relates generally to devices used to prevent damage to electrostatic sensitive equipment; and more particularly it concerns personnel grounding, so-called "wrist straps" useful in such applications.
The problem of preventing damage to electrostatic sensitive equipment is a serious one. As an example, in fabrication of electronic as well as other apparatus employing plastic parts, the problem of unwanted and destructive static build-up and arcing, which can lead to damaged electronic equipment, shocks to employees and fires, is acute. In the past, grounding wires have been used to conduct electrostatic charge build-up on personnel handling electronic parts to grounded members, and for this purpose wrist straps were attached to the arms of users to conduct charge to the grounding wires. Problems encountered included inadvertent wire disconnection from the grounding member and from the wrist straps, as when a worker moves his arm as a way to tension the wire, and wire breakage. One expedient to counter this problem was to wind the wire around the wrist strap, or to tape the wire; however, this was found objectionable, one reason being that it interfered with good electrical contact between the wrist strap and the user's wrist. The cost of equipment damage and reduced worker efficiency due to such static build-up is extremely high.